High-dose chemotherapy followed by autologous stem cell transplantation as a first-line therapy for high-risk primary breast cancer: a meta-analysis

Late Recurrence in Breast Cancer: To Run after the Oxen or to Try to Close the Barn?

Simple Summary

The initial treatment of early breast cancer has achieved important clinical results over time. However, late recurrences after many years of disease-free survival remain an open question, which has recently attracted the attention of a few researchers. The authors of this commentary suggest that the approach emerging from scientific meetings regarding this subject is marred by the lack of attention to recent clinical and laboratory data. The role of tumor dormancy and the dynamics of disease recurrence are presented here and a more general reflection on therapeutic approaches to cancer is proposed.

Abstract

The problem of late recurrence in breast cancer has recently gained attention and was also addressed in an international workshop held in Toronto (ON, Canada), in which several aspects of the question were examined. This Commentary offers a few considerations, which may be useful for the ongoing investigations. A few premises are discussed: (a) clinical recurrences, especially the late ones, imply periods of tumor dormancy; (b) a structured pattern of distant metastases appearance is detectable in both early and late follow-up times; (c) the current general paradigm underlying neoplastic treatments, i.e., that killing all cancer cells is the only way to control the disease, which is strictly sprouting from the somatic mutation theory, should be re-considered. Finally, a few research approaches are suggested.

High-dose chemotherapy and autologous bone marrow or stem cell transplantation versus conventional chemotherapy for women with early poor prognosis breast cancer

BACKGROUND

Overall survival rates are disappointing for women with early poor prognosis breast cancer. Autologous transplantation of bone marrow or peripheral stem cells (in which the woman is both donor and recipient) has been considered a promising technique because it permits use of much higher doses of chemotherapy.

OBJECTIVES

To compare the effectiveness and safety of high-dose chemotherapy and autograft (either autologous bone marrow or stem cell transplantation) with conventional chemotherapy for women with early poor prognosis breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group Specialised Register, MEDLINE (1966 to October 2015), EMBASE (1980 to October 2015), the World Health Organization's International Clinical Trials Registry Search Platform, and ClinicalTrials.gov on the 21 October 2015.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing high-dose chemotherapy and autograft (bone marrow transplant or stem cell rescue) versus chemotherapy without autograft for women with early poor prognosis breast cancer.

DATA COLLECTION AND ANALYSIS

Two review authors selected RCTs, independently extracted data and assessed risks of bias. We combined data using a Mantel-Haenszel fixed-effect model to calculate pooled risk ratios (RRs) and 95% confidence intervals (CIs). We assessed the quality of the evidence using GRADE methods. Outcomes were survival rates, toxicity and quality of life.

MAIN RESULTS

We included 14 RCTs of 5600 women randomised to receive high-dose chemotherapy and autograft (bone marrow transplant or stem cell rescue) versus chemotherapy without autograft for women with early poor prognosis breast cancer. The studies were at low risk of bias in most areas.There is high-quality evidence that high-dose chemotherapy does not increase the likelihood of overall survival at any stage of follow-up (at three years: RR 1.02, 95% CI 0.95 to 1.10, 3 RCTs, 795 women, I² = 56%; at five years: RR 1.00, 95% CI 0.96 to 1.04, 9 RCTs, 3948 women, I² = 0%; at six years: RR 0.94, 95% CI 0.81 to 1.08, 1 RCT, 511 women; at eight years: RR1.17, 95% CI 0.95 to 1.43, 1 RCT, 344 women; at 12 years: RR 1.18, 95% CI 0.99 to 1.42, 1 RCT, 382 women).There is high-quality evidence that high-dose chemotherapy improves the likelihood of event-free survival at three years (RR 1.19, 95% CI 1.06 to 1.34, 3 RCTs, 795 women, I² = 56%) but this effect was no longer apparent at longer duration of follow-up (at five years: RR 1.04, 95% CI 0.99 to 1.09, 9 RCTs, 3948 women, I² = 14%; at six years RR 1.04, 95% CI 0.87 to 1.24, 1 RCT, 511 women; at eight years: RR 1.27, 95% CI 0.99 to 1.64, 1 RCT, 344 women; at 12 years: RR 1.18, 95% CI 0.95 to 1.45, 1 RCT, 382 women).Treatment-related deaths were much more frequent in the high-dose arm (RR 7.97, 95% CI 3.99 to 15.92, 14 RCTs, 5600 women, I² = 12%, high-quality evidence) and non-fatal morbidity was also more common and more severe in the high-dose group. There was little or no difference between the groups in the incidence of second cancers at four to nine years' median follow-up (RR 1.25, 95% CI 0.90 to 1.73, 7 RCTs, 3423 women, I² = 0%, high-quality evidence). Women in the high-dose group reported significantly worse quality-of-life scores immediately after treatment, but there were few statistically significant differences between the groups by one year.The primary studies were at low risk of bias in most areas, and the evidence was assessed using GRADE methods and rated as high quality for all comparisons.

AUTHORS' CONCLUSIONS

There is high-quality evidence of increased treatment-related mortality and little or no increase in survival by using high-dose chemotherapy with autograft for women with early poor prognosis breast cancer.

High-Dose Chemotherapy and Autologous Hematopoietic Stem Cell Transplantation as Adjuvant Treatment in High-Risk Breast Cancer: Data from the European Group for Blood and Marrow Transplantation Registry

The aim of this retrospective study was to assess toxicity and efficacy of adjuvant high-dose chemotherapy (HDC) and autologous hematopoietic stem cell transplantation (AHSCT) in 583 high-risk breast cancer (BC) patients (>3 positive nodes) who were transplanted between 1995 and 2005 in Europe. All patients received surgery before transplant, and 55 patients (9.5%) received neoadjuvant treatment before surgery. Median age was 47.1 years, 57.3% of patients were premenopausal at treatment, 56.5% had endocrine-responsive tumors, 19.5% had a human epidermal growth factor receptor 2 (HER2)-negative tumor, and 72.4% had ≥10 positive lymph nodes at surgery. Seventy-nine percent received a single HDC procedure. Overall transplant-related mortality was 1.9%, at .9% between 2001 and 2005, whereas secondary tumor-related mortality was .9%. With a median follow-up of 120 months, overall survival and disease-free survival rates at 5 and 10 years in the whole population were 75% and 64% and 58% and 44%, respectively. Subgroup analysis demonstrated that rates of overall survival were significantly better in patients with endocrine-responsive tumors, <10 positive lymph nodes, and smaller tumor size. HER2 status did not affect survival probability. Adjuvant HDC with AHSCT has a low mortality rate and provides impressive long-term survival rates in patients with high-risk BC. Our results suggest that this treatment modality should be considered in selected high-risk BC patients and further investigated in clinical trials.

Adjuvant high-dose chemotherapy with autologous hematopoietic stem cell support for high-risk primary breast cancer: results from the Italian national registry

The efficacy of high-dose chemotherapy (HDC) and autologous hemopoietic progenitor cell transplantation (AHPCT) for breast cancer (BC) patients has been an area of intense controversy among the medical oncology community. The aim of this study was to assess toxicity and efficacy of this procedure in a large cohort of high-risk primary BC patients who underwent AHPCT in Italy. A total of 1183 patients receiving HDC for high-risk BC (HRBC) (>3 positive nodes) were identified in the Italian registry. The median age was 46 years, 62% of patients were premenopausal at treatment, 60.1% had endocrine-responsive tumors, and 20.7% had a human epidermal growth factor receptor 2 (HER2)-positive tumor. The median number of positive lymph nodes (LN) at surgery was 15, with 71.5% of patients having ≥ 10 positive nodes. Seventy-three percent received an alkylating agent-based HDC as a single procedure, whereas 27% received epirubicin or mitoxantrone-containing HDC, usually within a multitransplantation program. The source of stem cells was peripheral blood in the vast majority of patients. Transplantation-related mortality was .8%, whereas late cardiac and secondary tumor-related mortality were around 1%, overall. With a median follow-up of 79 months, median disease-free and overall survival (OS) in the entire population were 101 and 134 months, respectively. Subgroup analysis demonstrated that OS was significantly better in patients with endocrine-responsive tumors and in patients receiving multiple transplantation procedures. HER2 status did not affect survival probability. The size of the primary tumor and number of involved LN negatively affected OS. Adjuvant HDC with AHPCT has a low mortality rate and provides impressive long-term survival rates in patients with high-risk primary BC. Our results suggest that this treatment modality should be proposed in selected HRBC patients and further investigated in clinical trials.